Recently, Batt et al (25) redefined miillerianosis as "an organoid structure of embryonic origin; a choristoma composed of mUllerian rests--normal endometrium, normal
endosalpinx, and normal endocervix--singly or in combination, incorporated within other normal organs during organogenesis." A choristoma is a mass of histologically normal tissue that is "not normally found in the organ or structure in which it is located." (25) Thus, according to Batt et al, (25) the pathogeneses of mUllerianosis and endometriosis are deeply different, as endometriosis is endometrium shed outside the uterine cavity that invades the outer surface of organs, whereas mUllerianosis is endometrium (and at times also
endosalpinx and endocervix) misplaced within other organs during organogenesis.